import java.util.Hashtable;
import java.util.Enumeration;
...
// create a new Hashtable
Hashtable h = new Hashtable( 149 /* capacity */, 0.75f /* loadfactor */ );

// add some key/value pairs to the Hashtable
h.put( "WA" , "Washington" );
h.put( "NY" , "New York" );
h.put( "RI" , "Rhode Island" );
h.put( "BC" , "British Columbia" );

// look up a key in the Hashtable
String key = "NY";
String stateName = (String)h.get( key );
out.println( stateName );
// prints "New York"

// enumerate all the contents of the hashtable
Enumeration keys = h.keys();
while ( keys.hasMoreElements() )
   {
   key = (String)keys.nextElement();
   stateName = (String)h.get( key );
   out.println( key + " " + stateName );
   // prints lines of the form NY New York
   // in effectively random order.
   } // end while